This application relates to turbomachinery and in particular to high speed, small scale turbomachinery.
High-speed turbomachinery is used in many applications, including high pressure liquid centrifugal pumps, high-speed centrifugal gas compressors, gas turbines, liquid turbines, rocket turbopumps, car-engine turbochargers, aircraft auxiliary power units, jet engines, and stationary power generation devices. These devices usually include one or more rotating devices that transmit power from a rotating shaft into a working fluid, increasing the energy contained in the working fluid, or extract power from a working fluid and transfer that power into a rotating shaft, reducing the energy contained in the working fluid.
Turbomachines typically have rotating elements with outer diameters in the range of 3 inches (for turbochargers) up to several feet (for large jet engines, steam turbines, or hydroelectric turbines). However, similar devices have generally not been successfully designed or constructed that can operate at high speeds when the outer diameters of the rotating elements are one and a half inches or smaller. Design of devices in this size range has not succeeded, in part, because it is not currently possible to manufacture turbomachines with the precision and small features required to maintain high performance operation at these scales and speeds.